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An electrophysiology study, or EP study, is a test to see if there is a problem with your heartbeat (heart rhythm) and to find out how to fix it.
In this test, the doctor inserts one or more flexible tubes, called catheters, into a vein, typically in the groin or neck. Then he or she threads these catheters into the heart. At the tip of these catheters are electrodes, which are small pieces of metal that conduct electricity. The electrodes collect information about your heart's electrical activity. Your doctor can tell what kind of heart rhythm problems you have and where those problems are.
Sometimes the problem can be fixed at the same time. A procedure called catheter ablation uses the catheters to destroy (ablate) small areas of your heart that are causing the problem.
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An electrophysiology study is used to:
Tell your doctor if you:
Talk to your doctor about any concerns you have about the need for the test, its risks, how it will be done, or what the results will show. To help you understand the importance of this test, fill out the medical test information form( What is a PDF document? ).
Tell your doctors all the medicines and natural health products you take. Some of these can increase the risk of bleeding or interact with anesthesia. Your doctor will tell you which medicines to take or stop before your procedure.
If you take blood-thinning medicine, be sure to talk to your doctor. He or she will tell you if you should stop taking this medicine before your procedure. Make sure that you understand exactly what your doctor wants you to do.
Arrange for someone to take you home after the test. You may not have to stay in the hospital overnight.
Do not eat or drink (except for a small amount of water) for a few hours before the test. If you are taking any medicines, ask your doctor if you should take them on the day of the test.
Take off any nail polish. That will make it easier for doctors and nurses to check the circulation in your fingers and toes.
Be sure to empty your bladder completely just before the test.
You will feel a sharp sting when the local anesthetic is injected to numb your skin at the catheter insertion site.
When the catheter is inserted, you may feel a brief, sharp pain. The movement of the catheter through your blood vessel may cause a feeling of pressure, but it is not usually considered painful. You may feel your heart skip when the catheter touches the walls of your heart. This is normal.
The temperature in the catheterization lab is kept cool so that the equipment does not overheat. For many people, the hardest part of the test is having to lie still for an hour or longer on the hard table. You may feel some stiffness or cramping.
Don't be afraid to speak up if you're worried about anything during the test. The doctors, nurses, and technicians want to know exactly how you're feeling.
It's especially important to tell the doctor if you have any of these symptoms during or after the test:
You may have some soreness and bruising at the insertion site. It is normal for the site to feel tender for about a week. But call your doctor if:
An electrophysiology study is considered safe. The risks of this test are small.
The more common complications are not serious. They include bleeding or bruising where the catheters were put in.
Serious complications are rare. But they include extra bleeding after the test, puncture of the heart, and damage to the electrical system of the heart that requires a pacemaker.
Very serious complications, such as heart attack or stroke, are very rare.
This test is not usually done during pregnancy, because it involves X-rays. Radiation could damage the developing fetus.
Anytime you are exposed to radiation, including the low levels of X-ray used for this test, there is a chance of damage to cells or tissue. But the risk of this damage is usually very low compared to the possible benefits of the test.
An electrophysiology study will show whether you have an abnormal heartbeat that needs treatment. (Sometimes the treatment is done during the test.)
Reasons you may not be able to have the test or why the results may not be helpful include:
An electrophysiology study can be scary. You may find it helpful to talk to your doctor ahead of time about your fears. If you are awake during the test, you can ask questions and let your doctor and others know how you're feeling.
Other Works ConsultedChernecky CC, Berger BJ (2013). Laboratory Tests and Diagnostic Procedures, 6th ed. St. Louis: Saunders.Fischbach F, Dunning MB III (2015). A Manual of Laboratory and Diagnostic Tests, 9th ed. Philadelphia: Wolters Kluwer Health.Miller JM, Zipes DP (2015) Diagnosis of cardiac arrhythmias. In DL Mann et al., eds., Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 10th ed., vol. 1, pp. 662–684. Philadelphia: Saunders.Tedrow UB, et al. (2011). Electrophysiology and catheter-ablative techniques. In V Fuster et al., eds., Hurst's The Heart, 13th ed., vol. 1, pp. 1058–1070. New York: McGraw-Hill.
Current as of: April 9, 2019
Author: Healthwise StaffMedical Review: Rakesh K. Pai MD, FACC - Cardiology, ElectrophysiologyBrian D. O'Brien MD - Internal MedicineE. Gregory Thompson MD - Internal MedicineAdam Husney MD - Family MedicineMartin J. Gabica MD - Family MedicineJohn M. Miller MD, FACC - Cardiology, Electrophysiology
Current as of: April 9, 2019
Author: Healthwise Staff
Medical Review:Rakesh K. Pai MD, FACC - Cardiology, Electrophysiology & Brian D. O'Brien MD - Internal Medicine & E. Gregory Thompson MD - Internal Medicine & Adam Husney MD - Family Medicine & Martin J. Gabica MD - Family Medicine & John M. Miller MD, FACC - Cardiology, Electrophysiology
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